This invention relates to control devices for controlling the temperature, humidity, and/or other environmental conditions in an interior comfort space, and is more particularly concerned with an improvement to a wall thermostat. The invention is more particularly concerned with reconfigurable programmable thermostats, in which the settings for various heating and cooling modes can be programmed in and stored in an onboard microprocessor in the thermostat.
Wall thermostats are typically mounted on an interior wall of a house or other building to control the operation of a furnace, air conditioner, heat pump, or other environmental control apparatus. The thermostat is designed for continuous monitoring of room temperature and for adjusting the operation of the associated environmental control apparatus to keep the interior comfort space parameter (e.g., temperature) within in a temperature zone that is pre-set on the thermostat for a given day, time of day, or condition. In some applications, the thermostat may also be sensitive to other parameters, such as humidity or particulate level. The thermostat is connected to the furnace, air conditioner, and/or heat pump or the like by means of a run of thermostat wires which are connected to appropriate contacts or terminals on a terminal block inside the thermostat housing. There is typically at least a pair of conductors, and corresponding terminals on the terminal block, for the 24 volt AC thermostat power. There are usually several other terminals, also, to be connected via additional thermostat wire conductors to the furnace, air conditioner, heat pump, etc. A terminal is provided for the furnace and air conditioning indoor fan, for fan-only operation, and this is usually connected to a fan wire, i.e., a conductor identified with green-colored insulation.
The typical process of programming a configurable and programmable thermostat involves setting the thermostat into a program mode by pushing one or more keys or buttons, and then effecting the time and temperature setting for each mode before advancing to the next mode. The set up operation for a room thermostat can take fifteen or twenty minutes for each room thermostat. Usually, in a large construction operation where a large number of residential or office units are each being provided with an independent thermostat, an electrician installs the thermostats by connecting the thermostat wires, and then an HVAC specialist has to establish the settings on each and every one of the thermostats. This is a time consuming and rather tedious operation, and also requires a high-value employee to carry out the programming. At the same time, because the settings all have to be made manually, this is a source for human error.